While most amino acids are metabolized in the liver BCAAs are metabolized primarily by muscle. Despite their structural similarities the three branched chain amino acids have different metabolic routes. The breakdown of leucine is accomplished solely through fat pathways. Valine is broken down solely through carbohydrate pathways, and isoleucine through both. The different metabolic pathways of these three amino acids lead to varying requirements for each.

BCAAs, unlike most other amino acids, are metabolized in within muscle tissue, allowing them to be oxidized (used as energy) by muscle cells to produce cellular energy in the form of ATP. ATP is the primary source of energy that fuels muscle contraction and allows you to lift weights.


Since leucine, isoleucine, and valine are metabolized within muscle tissue allows them to be a quick energy source when the body needs it. There is a significant increase in BCAA metabolism during prolonged exercise simply because the body requires more energy during periods of stress such as training. This makes BCAAs incredibly effective when taken around the time of your workout routine.
BCAAs have been proven in many studies to be a potent performance enhancer, and as previously mentioned, BCAAs make a great energy source for working muscles because of their unique metabolism. This can have a positive impact on performance. Not only can BCAAs be used as energy themselves but they also enhance fat oxidation in glycogen depleted subjects. This allows individuals to train harder for longer without fatigue due to the higher energy demands being met. This goes for both high intensity training as well as endurance training.


the amino acid leucine has also shown promise for increasing insulin sensitivity. Essentially, insulin sensitivity ensures that the insulin within your body maintains its effectiveness. This leads to easier fat loss, more muscle growth, and defense against diabetes.